D because y (time spent) = 50 × x (distance travelled)
225÷4.5=50
x÷y=50
<span>a)
Acceleration of stone = 10
Integrate:
So velocity = 10t
Integrate again:
So distance from starting point = 5t^2
Distance from ground = 450-5t^2
b)
450 - 5t^2 = 0
9.48 seconds
c) velocity = 10t
Put the time into this to give:
94.8 m/s
d.
Velocity = 10t + 5
Integrate again:
5t^2 + 5t
Solve
5t^2 + 5t = 450
Gives 9 seconds</span>
Hey there!
<u>Use the quadratic formula to find the solution(s). x² + 2x - 8 = 0</u>
x = -4 or x = 2 ✅
<em><u>Quadratic</u></em><em><u> </u></em><em><u>formula </u></em><em><u>:</u></em><em><u> </u></em>ax² + bx + c = 0 where a ≠ 0
The number of real-number solutions <em>(roots)</em> is determined by the discriminant (b² - 4ac) :
- If b² - 4ac > 0 , There are 2 real-number solutions
- If b² - 4ac = 0 , There is 1 real-number solution.
- If b² - 4ac < 0 , There is no real-number solution.
The <em><u>roots</u></em> of the equation are determined by the following calculation:

Here, we have :
1) <u>Calculate </u><u>the </u><u>discrim</u><u>i</u><u>n</u><u>ant</u><u> </u><u>:</u>
b² - 4ac ⇔ 2² - 4(1)(-8) ⇔ 4 - (-32) ⇔ 36
b² - 4ac = 36 > 0 ; The equation admits two real-number solutions
2) <u>Calculate </u><u>the </u><u>roots </u><u>of </u><u>the </u><u>equation</u><u>:</u>
▪️ (1)

▪️ (2)

>> Therefore, your answers are x = -4 or x = 2.
Learn more about <u>quadratic equations</u>:
brainly.com/question/27638369
Answer: 32
Step-by-step explanation:
Ur whole be a for the following reasons